Process of making artificial stone.



20 In the STATEPACENT orrron WILLIAM FITZ CHARLES MASON, MCCARTY, OF PLEASANTVILLE, NEW YORK.

lPBOdESS OF MAKING ARTIFICIAL STONE.

No Drawing. I

To all whom, it may conce rn i Be it known that I, \VILLIAM F. C. M. Mc-

CARTY, a citizen of the United States, residing at Pleasantville, in the county of "Westchester and State of New York, have invented certain' new and useful Improvements in Processes of, Making -Artificial Stone, of which the following is a specification. This invention relates to artificial stone and has particular reference to a composi tion of this character adapted for use in building construction, and particularly in making tiles, columns,'panels, capitals and also'in making statuary, architectural orna- 1 ments, and the like.

Other objects and purposes of this invention will be apparent from the following description.

raotice of myprocess I employ silica, pre erably in the form of white sand, although some measure of success may be obtained by the employment of various silicates, as' for example, the silicate of magnesia. Silicates are for the purpose of this invention chemical equivalents of the silica which I prefer to employ, andsuch silicates are considered to be referred to by the term silica as herein employed. The silica or silicate is first subjected to treatment with a mixture of concentrated nitric acid and hydrofluoric acid, the mixturebeing preferably in the approximate proportions of forty-eight parts of nitric acid to fifty-two parts of hydrofluoric acid, but these proportions may be Widely varied. After mixing the acids the mixture is allowed to cool. The silica or silicate, preferably in powderedfc-rm, is mixed with it, preferably in 40 approximately the proportions of six pounds of the mixed acid. to each one hundred pounds of the silica. The mass is allowed to stand until the rains become softened so that they can be dattened between the finger and thumb. The resulting softened or plastic mass is then thoroughly mixed with silica, preferably in the proportions of about 20 p:.. by Weight of the plastic mass one hundred parts by weightof the silica and the mixture is allowed to stand until the 'm'ass acquires a noticeable degree of plasticity, such as that of soft putty. To the plastic mass is then added a hardening reagent, preferably an alkaline-earth com-- pound as lime oxid or calcined,magnesia, previously moistened with water to about Specification of Letters Patent.

' Application filed March 8, 1911. Serial No. 613,029.

oxid of zinc in water.

Patented May 6,1913.

the consistency of mortar. This hardening reagent-is added in the proportions which are shown by practice to give the best result, a matter readily determined'by test 0 with the particular materials undertreatment. Satisfactory results may however, be obtained by employing from 100 to 150 parts by weight of the. hardening reagent, not includingthe water, to one hundred parts 55 by weightof the plastic mass. The harder ing reagent is thoroughly incorporated in the plastic mass and the mixture allowed to crystallize and harden irisuitable molds, preferably molds with smooth glass or polished metal sides. I have found it advantageous to add an organic acid, preferably acetic acid, to the mass before it hardens. This acid may be added before 01 with the hardening reagent or after such hardening reagent is added, but before the mass hardens. The organic acid is preferably 3 added in proportions from one to three parts by weight of the acid to one hundred parts of the plastic mass. 0 "I have found'that a very attractive appearance is imparted to my artificial stone by brushing over the surface thereof after such mass has wholly or partially set, but before it is dry, a solution or emulsion of 35 v The appearanceof the product is still further improved by following this treatment with zinc o'xid with a similar treatmentwith a solution of chlorid of zinc, The finished mass requires from about twelve to thirty-six hours to thoroughly harden, after which it maybe handled and used the same as marble or hther stone.

While I have glcscribed in detail the )re- 9 5 ferred proportions and ingredients, it is to be understood that lsuch proportions may be widely varied and that chemical equivalents of the re-agent may be employed within the spirit of my invention and without departing from the scope of the appeneded claims. Having thus described my invention, I claim i l. The herein described process which consists in adding to silica a softening reagent consisting of nitric and hydrofluoric acids, adding to the resulting plastic mass a hardening reagent comprising an alkalineearth, compound, and permitting the resulting mass to harden. The herein described process, which consists in adding to silica a softening l'u- .Q I I 1,060,614

agent, mixin the resulting softened mass with silica, a ding to the mixture a hardenmg. reagent, and permitting the resulting an alkaline-earthmetal, and permitting the" resulting mass to harden. 4. The herein described process, which I consists in adding to silica a softening reagent comprising nitric and hydrofluoric acids, ixinggthe softened masswith silica.

and ad ing to the mixture a'h'ardening reagent comprising a' compound of an'alkaline-earth'metal, and permitting the mass to harden. a i Y ,1 .5. i'lhe.fherein described process, which v eonsists in-.ad ding.1to silica a softening re-- agentg ihntorporatlngin the mass a compound of iinalkaline-earth metal and an organic acid, and permitting such mass to' harden. v

. '6. The herein described process, which,

: consists in adding to silica -a softening re- I "agent comprising nitric and hydrofluoric -acids, adding to the resulting plastic mass a hardening reagent comprising 'a 'com pound of analkaline earth metal and an organic acid, and permitting-the mass to harden." 'i I i 4 7. The herein 'descrilecdprocess, which consists 'iniadding to silir a softening -re agent comprising nitric. and hydrofluoric acids, adding to the resulting plastic mass a hardening reagent comprising an alkalineearth compound and an organic acid, applying to the surface of the mass a solution of zinc oxid, and permitting the said mass to harden.

8. The herein described process, which consists in adding-to silica a softening reagent comprising nitric' and hydrofluoric ac1d, 1ncorporat1ng in the softened mass 2. hardenmg reagent comprising a saltof an alkaline-earth metal and an organic acid,

applying to the surface of the mass a solution of oxid of zinc and thereafter applyin to the said surface a solution of chlorid o zinc, and permitting the mass to harden.

9. The herein described process, which" consists in adding to silica a. softening reagent comprising nitric and hydrofluoric acids, mixing thesoftened mass with silica, adding to such mixture a hardening reagent comprising an alkaline-earth compound and an organic acid, applying to the surface of the mass a solution of zinc oxid and thereafter applying to the surface .of such. mass a solution of zinc chlorid, andpermitting 7 the mass to harden.

In testimony whereof I atlix my signature in presence of two witnesses.

'- WILLIAM rrrz CHARLES MASON ncc n'ri.

Witnesses: Gno. H. HAIGHT, J12,

GEORGE W. DERLY. 

